If the waters are as polluted as much as the media is saying (and showing) I just don't see how they can have any in-the-water activities. The Brazilian authorities state all is well, but I don't see any of them drinking the water or even stepping in it.

IIRC the Chinese delegation reported that their rooms were the dirtiest and most dysfunctional they had ever seen. I do recall the media reported the same at the last USSR Olympics.